As a fluid control device used to supply a plurality of types of material gases by switching between them as appropriate to a processing chamber, there is a known fluid control device that includes a main body having a rectangular parallelepiped shape, main gas input-output ports and vent gas input-output ports provided at both ends in the longitudinal direction of the main body, the main gas input-output ports being disposed at a certain distance from the vent gas input-output ports in the width direction, a main gas passage communicating between the main gas input-output ports, a vent gas passage communicating between the vent gas input-output ports, a plurality of sub-gas inlets provided at predetermined intervals in the longitudinal direction on one side of the body, a total of two rows of on-off valves arranged in the width direction (two on-off valves are disposed in each of positions corresponding to the sub-gas inlets), a plurality of first sub-gas inflow passages leading to the inlets of the on-off valves in the first row from the sub-gas inlets, and a plurality of second sub-gas inflow passages leading to the inlets of the on-off valves in the second row from the sub-gas inlets (for example, PTL 1).
In the fluid control device in PTL 1, the main body includes a plurality of central passage blocks and two side passage blocks extending in the front-rear direction, in which the main gas passage and vent gas passage are formed linearly and connected to the outlets of the on-off valves via the passage orthogonal to the main gas passage and vent gas passage.